@misc{indiciaeeb916614c2a4,
  title = {Feynman propagator for spin foam quantum gravity.},
  author = {Daniele Oriti},
  year = {2005},
  doi = {10.1103/physrevlett.94.111301},
  url = {https://pubmed.ncbi.nlm.nih.gov/15903843/},
  note = {Source identifier: 15903843}
}